Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Vibronic Coupling in Semi-Fluorinated Alkanethiol Junctions: Implications for Selection Rules in Inelastic Electron Tunneling Spectroscopy

Author(s)

J M. Beebe, H J. Moore, T R. Lee, James G. Kushmerick

Abstract

Determining the selection rules for the interaction of tunneling charge carriers with molecular vibrational modes is important for a complete understanding of charge transport in molecular electronic junctions. Here, we report the low-temperature charge transport characteristics for junctions formed from hexadecanethiol molecules having varying degrees of fluorination. Our results demonstrate that C-F vibrations are not observed in inelastic electron tunneling spectroscopy (IETS). Because C-F vibrations are almost purely dipole transitions, the insensitivity to fluorine substitution implies that Raman modes are preferred over infrared modes. Further, the lack of attenuation of the C-H vibrational modes with fluorine substitution suggests that either the scattering cross section is not an additive quantity or the physical position of a vibrational mode within the junction influences whether the transition is observed in IETS.
Citation
Nano Letters

Citation

Beebe, J. , Moore, H. , Lee, T. and Kushmerick, J. (1970), Vibronic Coupling in Semi-Fluorinated Alkanethiol Junctions: Implications for Selection Rules in Inelastic Electron Tunneling Spectroscopy, Nano Letters (Accessed August 9, 2022)
Created August 26, 2016, Updated February 17, 2017